Questions & Answers

Hello fellow professionals,

I’m currently working on a project where we need to float a floor that has a plywood sub-grade. The goal is to achieve a 3/4-inch thickness throughout the floor area before installing 3/4-inch stone tiles. Our team is looking for the best method to ensure a perfectly even and plumb surface to guarantee a durable installation.

Here’s our initial plan:

1. Sub-grade Preparation: We’re considering using black paper as the initial layer.

2. Lath Material: We’re thinking of using some sort of lathing, but we’re concerned about the risk of metal wire rusting during the curing process.

3. Efflorescence Prevention: We want to avoid any issues with efflorescence that might seep out after the stone installation.

4. Waterproofing: We’re also planning to use Schluter Ditra membrane over the float for added waterproofing and uncoupling.
   

Given these considerations, I’d like to ask:

• What is the best approach to floating this floor to achieve a stable, even, and plumb surface?

• Are there any recommended materials or methods to avoid rusting of lath and prevent efflorescence during and after the curing process?

• Is our approach of black paper, float, Ditra membrane, and stone installation sound, or is there a better method to guarantee long-term performance?
  

Any insights, advice, or shared experiences would be greatly appreciated!

Thanks in advance for your help.